package com.bys.service.impl;

import com.bys.service.LoadBalancer;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Service;

import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

@Service
public class LoadBalancerImpl implements LoadBalancer {
    private AtomicInteger atomicInteger = new AtomicInteger(0);
    public final int getAndIncrement(){
        int current;
        int next;
        do{
            current = this.atomicInteger.get();
            next = current >= Integer.MAX_VALUE ? 0 : current + 1;

        }while(!this.atomicInteger.compareAndSet(current,next));
        System.out.println("======第"+ next+ "===次" );
        return next;
    }

    @Override
    public ServiceInstance instances(List<ServiceInstance> serviceInstances) {
        int index = getAndIncrement() % serviceInstances.size();
        return serviceInstances.get(index);
    }
}
